Cartridge-powered piston type tool



ug. 23,` 1960 P. R. HAsKELL ETAL 2,949,898

cARTR1DGEPowERED PIs'roN TYPE Toor.

Original Filed May lO, 1955 2,949,898 CARTRIDGE-POWERED PISTON TYPE TOOL3 Claims. (Cl. 123-24) This invention pertains to improvements inexplosively actuated or cartridge powered tools, and provides a tool ofthis type of unique construction which is characterized by extremecompactness, lightness in weight and ease of manipulation with a minimumof effort, and which furthermore is substantially foolproof.

This application is a division of our copending application Serial No.507,281, filed May 10, 1955.

In its various modifications the tool of the invention is adapted forperforming a wide variety of work functions, such as the cutting ofconduit, bar stock and heavy cable, etc., the punching of holes,riveting, the swaging of terminals or sleeves on electrical cables forterminating or uniting the same, the uniting of electrical conduitsections by means of an interposed coupling member, as well as thesecuring of threaded members on electrical conduit terminations, etc.

The tool of the invention comprises in its essentials and in accordancewith a preferred modiiication, an elongated frame member of steelcomprising a tubular or barrel section terminating at one end in ahook-like retainer arm of substantially C-shaped configuration formounting a work piece to be operated upon. Within the barrel section isslidably displaceable a piston which mounts on its forward end a worktool, such as a cutter blade, hole puncher, cable swager, rivetingplunger, etc. The

tubular section of the frame is of reduced aperture at its u muzzle endto provide a shouldered impact face for arresting forward motion of thepiston thereat. The muzzle end is, in addition, appropriately aperturedfor passage of the work tool therethrough to work engaging position witha Work piece held in the retainer arm.

The breech end of the .barrel section is closed by vmeans of a barrelplug inser'table therein, this plug having a anged head which overliesthe end of the frame thus to prevent incorrect or wrong-end-to assembly.T he breech end of the frame as Well as the barrel plug are transverselyapertured and counterbored for insertion of a relatively massivecartridge chamber plug having an enlarged head which seats in thecountcrbore, thus again preventing incorrect assembly. This chamber plugcontains a bore extending axially through the head for insertion of acartridge, whereby the tool is cartridge chambered substantially atright angles to the barrel axis, a feature which permits ofsubstantially shortening the effective length of the tool and eliminatesthe necessity for safety precautions such as are otherwise required inconventional constructions wherein the cartridge chamber is aligned withthe barrel. The cartridge chamber has access to the barrel through asidewall outlet and an aligned bore comprising an explosion chamber,extending through the end of the barrel plug.

A novel feature of the invention to which the present application isdirected, comprises means yfor adjustably varying the volume of theexplosion chamber, whereby the force impelling the piston from a blankcartridge of standard charge may be adjustably preset in accordance2,949,898 ,Patented Aug.,23, 1960 with the work force segment of thetool mounted on the pistons.

IIn the accompanying drawings:

Fig. 1 is a longitudinal sectional elevation through a tool assembly towhich the invention is particularly applicable.

Figure 2 is a longitudinal sectional elevation of the breech end of atool assembly, similar to Figure 1, but showing the modification of thecartridge chamber according to the present invention for varying theexplosive action from a standard cartridge.

Figure 3 is a detail in side elevation of the adjusting knob shown insection in Figure 2; while Figure 4 is an end view of the adjusting knobof Figure?, with a portion broken away to illustrate suitable detentindexing means for positioning the knob at various settings.

Referring to Fig. l, the tool assembly thereof cornprises a frame,identified generally by numeral 1, consisting of a tubular frame portion2 extending from the breech end at the left to the muzzle end at theright, and a C-frame extension comprising a work support 3 in generallongitudinal alignment with the frame portion 2 and connected therewithby a curved shank 3a. The breech end of the frame portion is of slightlyenlarged bore as compared to the muzzle end of the frame portion 2 andthus provides a shoulder at 4, against which a relatively short sleevebarrel 5 is held by means of a barrel plug 6, inserted in the breech endof the frame. The barrel plug is locked in the position shown by acylindrical cartridge chamber plug 7 which extends transversely of thebarrel axis through suitable holes 8, 9 drilled in the barrel plug andthe breech end of the frame portion 2, respectively. The cartridgechamber plug 7 is provided with Van enlarged head A10 which seats in acounterbore 11 of the barrel plug, thus to maintain the assembly lockedin position as shown in Fig. 1.

The mouth of the chamber plug is radially slotted to receive an ejector(to be described), and to locate chamber plug 7 in proper longitudinaland radial position in the bores 8, 9, the cylindrical wall of the plugis notched for reception of a pin 12, backed by a small compressionspring 13, mounted in an axial bore 13a of the barrel plug 6.

A piston 14 is slidably disposed in the sleeve barrel 5, and to which issecured a cutter blade 15 positioned in `advance of the piston in theframe portion of smaller inside diameter. The cutter blade is slidablein grooves 16, 17 extending along the upper and lower portions of theframe barrel.

The cutter assembly 15 shown as a cutter blade is secured to or formedintegral with a shank 18, which eX- tends through a central sleevemember 18b of the piston 14 and is secured to the piston by means of Iapiston cap 19 threaded onto the breech end of the shank 18.

The breech end of the piston cap 19. terminates in a protuberantextension 29 of considerably smaller diameter than fthe piston 14, whichextension in the action or firing position, rests in a conforming bore20a drilled in the inner end of the barrel plug 6.

The piston and cutter blade assembly 14, 15, is resiliently held inplace by means of a resiliently mounted detent 2012 which engages theupper edge of the cutter blade as shown.

The cartridge chamber 7 has formed in the upper portion thereof a bore21 for insertion of a blank cartridge, as at 22, the cavity below thecartridge forming an explosion chamber which has access through alignedopenings in the sidewall of the chamber plug and the forward end of thebarrel plug, as at 22a, 23, to the bore 20a of the barrel plug.

Thus when the cartridge is tired, the piston and cutter assembly 14, 15,is impelled progressively forward until the pointed end of the cutterblade has advanced to the position to serve the conduit. The piston andcutter assembly is thereupon brought to rest by engagement of theforward end of the piston 14 with a shouldered impact face 24',` ofconforming configuration formed at the muzzle end of the tubular framesection 2, 4at which the bore is tapered to an outlet passage 25 ofrelatively small bore through which the explosion gases escape.

The frame 1 is provided with `a cover or carriage S0 having in endvView, a relatively flat C-shaped configuration, with turned in lowerlateral edges. The frame section 2 is correspondingly grooved along theupper edges of its opposite outer sidewalls, whereby the cover may beslid endwise onto the trame in vertically locking engagement therewith.

Mounted on the breech end of the cover is the firing unit 55'. Mountedadjacentv thereto is a cross slide protective device 56 which istransversely adjustable to locking, ejecting and firing positions, andwhich prevents firing except when adjusted to the position lastmentioned, as described in detail in our parent application aforesaid.Resiliently mounted on the muzzle end of the cover is a clamping deviceS7 which clamps the conduit 150 to be cut in the G terminus or worksupport 3 of the frame when the cover is longitudinally positioned withrespect to the frame -as shown in Fig. 1.

Referring now to Figs. 2-4, inc., there is shown a modication of thetool construction above described Vfor varying the explosion force onthe piston 14 from a blank cartridge 22 of standard charge. In thisembodiment the sidewall of the cartridge chamber plug 210 is drilledthrough and counterbored opposite the outlet passage to slidably receiverespectively the tip 211 and flanged head 211a of a screw 212 threadedthrough the barrel plug 213 4and provided at its outer terminus with anindexing head 214. The barrel plug is also counterbored, as at 215, forslidable reception of the flanged head 211a. Retraction of flange 2110iin counterbore 215 adds to the chamber volume any desired fraction ofthe volume of said counterbore; thus, enabling a control of the burningcharacteristics of the powder and the maximum pressure developed therebythroughout a range determined by the volume of counterbore 215. In thisway the force impelling the piston from a blank cartridge of standardcharge may be adjustably preset in accordance with the work forcerequired of the tool mounted on the piston. As shown in Fig. 3, the knob214 is indexed, as at 216, in proportion to the variation in eX-Vplosive force resulting from any given adjustment. Also referring toFigs. 2 and 4, the barrel plug has resiliently mounted therein apositioning detent 217 adapted to engage peripherally spaced notches 218of the knob for presetting the knob in accordance with desired setting.

What is claimed is:

1. In a tool explosively actuated by a powder charge: a barrel, a pistonretained in and displaceable along said barrel, means lincluding anexplosion ch-amber for said powder charge, disposed at the breech end ofsaid barrel for explosively impelling said piston along the barrel, saidchamber including a bore for reception of a cartridge containing saidpowder charge, together with means for adjustably varying the volume ofsaid explosion chamber, thereby to vary the impelling force on saidpiston fro-rn a cartridge of constant powder charge.

2. In a tool explosively actuated by a powder charge: a barrel `forreception of a piston-like element displaceable therealong, meansincluding an explosion chamber for said powder charge, disposed at thebreech end osaid barrel for explosively impelling said piston-likeelement along the barrel, said chamber including a bore for reception ofa cartridge containing said powder charge, said chamber being ofsubstantially greater volume than said bore and including means foradjustably varying the volume of said explosion chamber, thereby toadjustably vary the impelling force on said piston-like element from acartridge of constant powder charge.

3. In a tool explosively yactuated Iby a powder charge: a barrel forreception of a piston-like element displace- -able therealong, meansincluding an explosion chamber for said powder charge, disposed at thebreech end of said barrel for eXplosively impelling said piston-likeelement along the barrel, said chamber including a bore for reception ofa cartridge containing said powder charge, together with means foradjustably varying the volume of said explosion chamber, thereby toadjustably vary the impelling -force on said piston-like element from acartridge of constant powder charge, said means including a cavity-likeextension of the explosion chamber of substantially constantcross-section, a piston displaceable in said cavity and means for sodisplacing said piston and including indexing means for adjustablypositioning said piston and for indicating said positioning.

References Cited in the file of this patent UNITED STATES PATENTS253,709 Hutchinson Feb. 14, 1882 830,099 Packard Sept. 4, 1906 2,080,720Jahnke May 18, 1937 2,140,214 Temple Dec. 13, 1938 FOREIGN PATENTS169,919 Switzerland Sept. 1, 1904 714,871 Great Britain Sept. 1, 1954

